Heating element support



p 21, 1948, H. A. MULVANY HEATING ELEMENT SUPPORT Filed ,April 26, 1946 Y INVENTOR. 9 HARRY A. MuLyAA/r I II I.

A 7' TORNEV Patented Sept. 21, 1948 STA-T ES PATENT F F ICE:

" i HEATING-ELEMENT- SUPPORT Harry A. Mulvany, Berkeley, Calif.

' Application April 26, 1946,Sria',l No'.'-665,076

. 6 Claims.

\ This invention relates to a heating-element support, and especially to improvements. in the heating element support disclosed in my former Patent Number. 1,682,402;entitled: Heating ele= ment support, issued August 28, 1928.

The heating element support disclosedin my former patent consistedrof an" elongated base memberin'the form of a brick which was constructedof ceramic or refractory material, and which was provided with.'a,:plurality of spaced apart" ribs on one face and extending from end to'endithereof. A ribbon form of electrioheating elementv was wound in zigzag form about the ribs and supportedthereby and lugs were formed at each 'endofeach rib to retain't'he ribbon elements from slipping or working oh the ends of. the ribs; In actua'l practice it was, however, found that the elements 1 would gradually lengthen; during prolongeduse due to the intermittent heating andcooling-effectaan'd as they gradually. lengthened, they would work off the ends of one or more lugs :and finally contact each other with .a short circuit as the result, this being particularly the case when the elementsswere mounted'in-the ceil ingor vertical walls of an electric furnace or heater.

The object of the present invention is to improve =on' the form of heating element support disclosed in my prior patent, andparticularly to lock'or securethe ribbon formed heatingzelement-s fromworking off the ends of thesribs, and more specifically stated, toprovide 3, lug at'the end of each rib and in conjunction therewith "a V-shaped lugwl'iich limits elongationmovement of the rib?- bon'eleme'nts with relation to the first named-lugs tosuch an extent thatztheiribbon elements cannot work off or over the first named lugs.

:The heating element supportzforming the sub= ject matter of the present inventionis shown by wayxof'illustration in the accompanying drawings in which: 1 Fig-'1 is aperspective view showing a single unit type :of electric resistance heating element sup port; Fig. 2 is a perspective "view showing a triple typeof'ielectric .resistancexheating element support;

Fig. 3 is a side elevation of Fig. 1 or 2;

Fig. 4is'a front view'of Fig. 2;

Fig. 5 .is a. cross-section takenon line V -V of Fig. 2; and, i

Fig. 6 is a perspectiveview of the ribbon form offelectric resistance heating element employed.

Referring to the drawings in detail, and particularly Fig. 1, A'indicates the base portion of a heating element support and 2 and tend or head members formed at opposite'endsof the 4 base. Also formed on the base and extending substantially from end to'end thereof is a rib 4. This rib tapers in cross-section from the-top to the bottom so as to present inclined side surfaces and to reinforce and-increase the strength of the i 2 rib;-:-. A finger '5' is .formed'at each end of the rib, and" these fingers are: spaced from the base to form a'recess fi at each end-of the ribforthe reception .and' 'retention of a heating element hereinafter to-be described. The fingers-6 are also spaced with relatien to a v-shaped lug 1 formed on each head member, and'arestricted space 8 or passageway is thus formed at theend of 'each'finger to permitapplioation'of the heating element, heretoforereferred to.

In Fig. lthe basesection is illustratedas being comparatively long and narrow'and as supporting a single? rib suchzasindicated at 4; In Fig; 2 the base". has been'widenedzand three ribsare em- "ployedas: indicated at 4,-4aand' lb. The base may, however, be m'aterially widened when de' sired,- andany number of ribs maybe employed. .Illi :actual practice itrwill be understood that theheatingelement-support described and illustr-ated mayebe. employed in numerous electric heating. installations such as domestic electric airiheaters, radiant heaters, electric furnaces'and the like. Where theheating element support is employed" in an ordinary domestic electric air heater; one-or more blocks such as shown in Fig. lior 2 are placed vertically side by side and are secured within the heater in-this position by metal clampsror byany other: suitable means; The heating-element 1 supports when thus installed are readyaforrthereception ofthe electric resistancedieating element. Thetype preferably employed iaa. ribbon :form'of element such as shown in Fig. 6. It is comparatively wide in proportion to itsfthiclmessand "as such :is almost as flexible asa'ribbon; hence the name ribbonformof electricwresistance: heating element. :.By.'referringrtoFig; 4 :theribbon'element is indicated at B. The widening of the element may start 'atr the point 9. -It is then run up alongside ofnthe rib 4b and? the edgeof the ribbon is then slipped edgewise --through the space 8 formed between'the'finger Band the-V-shaped lug 1. It thus enters the recess fi: at the upper end-of the ribland'ris pulled tightlyinto said recess and thenit isfipassed down between theribs id-and 4b where itsis: agalnwpulled :through the space betweensth'e lower'finger and'the rib lb andthe Vv-shapedluglso as to enter the recess at the lower end oftheribvfla. It is then run upwardly between-the 'ribs i and a and then through the recess at the upperend of the rib 4. This method of windingrof the-'ribbonis continued until the entire: series of heating element supports are wound. The opposite ends of the ribbon-are then connected"toflterminal members, not shown, to which electric current is supplied in any suitable manner.

By referring to Fig. 3v it .will be noted that the V-shaped lugsfl "extend partially into the'recesses 6 formedattheopposite ends of the rib 4, hence when the-ribbon starts toelongate; it will'finally reach a point where it ests on-or'contacts the V-shaped lugs 1, and if further elongation takes place, the ribbons will merely buckle or bow to a certain extent in the Spaces between the ribs. Obviously, if the heating element supports are vertically disposed, the ribbon form of element which is wound in zigzag form around the ribs will tend to hang in loop-like form from the upper ends of the ribs. Hence, the greater tendency When elongation takes place is to work off the fingers 5 at the lower ends of the ribs but the loops formed at the lower ends of the ribbon cannot reach the lower ends of the fingers 5 as they contact the V-shaped lugs which project partially into the recesses 6 and as there is little, if any, chance of the looped lower ends of the ribbons becoming cocked or tilted to such an extent as to work out of the spaces 8, it is obvious that no matter how much elongation takes place, there is little or no chance for the ribbon form of element to ever free itself with relation to the fingers 5 and the lugs l.

The heating element supports, as previously stated, are placed side by side when installed in a furnace, heater or otherwise. They may be clamped or mortared into position or otherwise secured and a single unit block such as shown in Fig. 1 or multiple unit blocks, such as shown in Fig. 2, may be employed as conditions may demand. In any instance, where the blocks are placed side by side, a series of parallel interspaced ribs will be presented and the heating element will be supported by the ribs and will be either bent or wound to form a zigzag type of unit. While a ribbon type of heating element is illustrated, it should be understood that a helically r wound coil or any other suitable type of element may be employed. The brick or heating element support illustrated may be constructed of any refractory insulating material. It is exceedingly simple and substantial in construction and permits ready application of a heating element. The ribs form the support for the heating elements in certain instances and the ribs together with the head members 2 and 3 or lugs 1 formed thereon serve as supports. In other instances the vertical height of the ribs is in practically every instance greater than that of the diameter of the heating element coil or the width of the ribbon. This is also important as the ribs form shields or spacers between each section of the heating element, thus shielding adjacent coils or sections of the heating elements against radiation. By such shielding the excess temperatures in the elements proper is avoided and the temperature of the electric elements will, furthermore exceed the temperature of the furnace 0r heater by an exceedingly small increment. On the other hand where shielding is eliminated, the temperature of the adjacent elements is materially raised by radiation from one to the other and the amount of electric motive force which may be passed through the heater is materially reduced, and while this and other features of the invention have been more or less specifically described and illustrated, it should be understood that changes may be resorted to within the scope of the appended claims and that the materials and finish of the several parts employed may be such as the experience or judgment of the manufacturer may dictate or varyin conditions or uses may demand.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. An electric heating element support comprising a rectangular shaped base member, a vertically disposed rib formed on one face of the base member and extending substantially from end to end thereof, a finger formed at each end of the rib and spaced from the base member to form a recess at each end of the rib, a head member at each end of the base and spaced away from the adjacent finger, and a lug on each head member extending partially into the recess at the adjacent end of the rib.

2. An electric heating element support comprising a base member, a vertically disposed rib formed on one face of the base member and extending substantially from end to end thereof, a finger formed at each end of the rib and spaced from the base member to form a recess at each end of the rib, a head member at each end 0! the base and spaced away from the adjacent finger, and a V-shaped lug formed on each head member and extending partially into the recess at the adjacent end of the rib.

3. An electric resistance heating element and a support therefor comprising a rectangular shaped base member, a plurality of vertically disposed spaced ribs formed on one face of the base member and extending substantially from end to end of the base member, a finger formed at each end of each rib and spaced from the base to form a recess at each end of each rib, a flexible electric heating element wound in zigzag form about the ribs and seated in the recesses formed at the ends of the ribs, and means at each end of the base projecting partially into the recesses formed at the ends of the ribs, said means engaging and retainin the heating element in the respective recesses when said element becomes elongated.

4. An electric resistance heating element and a support therefor comprising a rectangular shaped base member, a plurality of vertically disposed spaced ribs formed on one face of the base member and extending substantially from end to end of the base member, a finger formed at each end of each rib and spaced from the base to form a. recess at each end of each rib, a flexible electric heating element wound in zigzag form about the ribs and seated in the recesses formed at the ends of the ribs, and a supporting member at each end of the base, said supporting member formin a. substantial closure for the recesses formed at the ends of the ribs to prevent the heating element when elongated from working out of the recesses.

5. An electric heating element support comprising an elongated base member, a longitudinal rib thereon, a finger formed at each end of the rib and spaced from the base member to provide a recess, and lugs projecting from the base member and substantially overlying the recesses leaving only restricted passageways.

6. An electric heating element support comprising a base member, a rib thereon, a finger formed at each end of the rib and spaced from the base member to provide a recess, head members projecting from the base member and overlying the recesses, and lugs projecting from the head members into the recesses.

HARRY A. MULVANY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,087,198 Steward Feb. 17, 1914 2,076,485 Streysman et al Apr. 6, 1937 

